Transcription, replication and DNA repair in the context of nuclear and nucleolar architecture

Main objectives

To characterise nucleoprotein composition of telomeres and telomerases, and examine interactions between telomere components, including quantitative biophysical approaches

To clarify connections between dynamics of telomere composition and DNA damage response

To explore evolution of telomeres, telomerase and alternative mechanisms of telomere maintenance

To investigate epigenetic processes involved in the regulation of genome transcription, replication and repair, and in telomere maintenance

To decipher functional links between chromatin assembly and genome stability

Content of research

Chromatin is a supramolecular complex of DNA, proteins and other associated molecules (e.g. RNA species). It is the building material of chromosomes, which can be observed during cell division in their most condensed state. Chromatin was first discovered in plant cells – as were the cells themselves, or genes.

Since eukaryotic genomes are folded into chromatin, all genome functions occur in the context of this highly dynamic structure. Understanding processes such as DNA replication and repair, transcription or cell differentiation thus requires understanding structure and function of chromatin, and its specific domains like centromeres, telomeres or nucleoli.

While the nucleotide sequence of the DNA component of chromatin constitutes the genetic material of the cell, the other chromatin components (and also modifications of bases in DNA itself) participate in so-called epigenetic functions. These include spatiotemporal regulation of gene activity and DNA replication, correct and precise segregation of genetic material to daughter cells, maintenance of chromosome stability, and protection of genetic material from damage. Importantly, the chromatin structure compacts several metres of genomic DNA to fit the size of a cell nucleus (several microns in diameter) while keeping it functional despite the high degree of compaction (up to105 fold).

Our research group integrates studies in the field of telomere biology, chromatin structure and epigenetics. Using unique features of plant systems (namely their high developmental plasticity), and their comparison to yeast or animal models, we aim to characterise pathways involved in the control of chromosome stability and distinguish between specific and general mechanisms involved. Outcomes of our studies (e.g., understanding mechanisms contributing to genome stability, aging or adaptation to changing environmental conditions) can be applied in agriculture, biotechnologies or medicine